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Discussion Starter #1
Hey, later this month I'm planning a trip. It's about 130 miles but there happens to be a mountain in between. I should have a plug available to me at my destination.

My plan currently is to use normal mode till I reach 50% then go into hold mode until I reach the summit and the switch back to normal mode for the remainder of the trip in order to bank the regen on the way back down. The elevation change after the summit isn't as aggressive as the climb up. the summit is about 5,000' and only going down to 3,500'. The return trip will be a different story since I'll be dropping all the way down to 200' when I reach home. I'll probably still use the same strategy for the trip back though unless someone has a better idea.

So now that you know my route I do have a couple questions.

Is there a benefit to using mountain mode as opposed to using half the battery then switching hold mode?

Are there signs that I may be pushing the volt to hard up the mountain?

Anyways, I'm probably over thinking this but that's what I like about the car. It's fun strategizing things to make it the most efficient. :cool:
 

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I would think you would want to be in MM for the trip and if the battery never actually gets below 40% it will never overdrive the ICE to keep the charge up on the battery. The car would, in effect, run like it was in Hold mode, but have the MM setting already engaged as a backup if it needs it. No need to risk running in to a limited propulsion situation if you don't have to.
 

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1) Is there a benefit to using mountain mode as opposed to using half the battery then switching hold mode?

2) Are there signs that I may be pushing the volt to hard up the mountain?

Anyways, I'm probably over thinking this but that's what I like about the car. It's fun strategizing things to make it the most efficient. :cool:
1) Not really. Mountain mode was intended to enable you to build up a small battery reserve in case you are about to start a long or steep ascent with a fully depleted traction battery. Since you will have the planned ahead and will have a 50% battery SOC you won't need mountain mode. If you want to start the ascent in MM instead of Hold mode then the battery will deplete to about 2 bars on the meter and then the Volt will maintain this level of charge in the battery. (The 40% SOC only applied to MM on the Gen 1 Volt. The Gen 2 Volt gas engine is more powerful than on the Gen 1, rarely needs any extra assist from the electric motor(s). On the Gen 2 Volt MM will only maintain about 15 - 20 % SOC (about 2 bars on the meter.)

2) You can observe the engine coolant on the Driver Information Console. Normally this would peak at ~205F. If the engine is running hard and the coolant temperature climbs above ~240F you might want to slow down your ascent. Turning off the AC won't help much because the AC compressor is electric but turning on the cabin heat will help dissipate the excess engine heat.

2) If you see any smoke coming from your tailpipe whether the smoke is black, blue or white this is not normal.
 

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Just start your trip in mountain mode. Let the System do the rest. Starting in Mountain mode automatically sets your hold level too slightly less than 50% you will burn off the top halve then it automatically switches to Mountain/hold level. You don’t need to remember to do anything. When you regen going down the other side you will likely add some green bars. Once that seems to peak you can switch back to normal mode if you want too.


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I would aim for "0" battery charge at my destinations, so try to arrive at the summit at "0" charge, regen enough in the descent to finish the trip on battery. if you run out of charge prior to your destination that's OK-- gas consumption on level or downhill is minimal. On the return trip, assuming full charge try this: hold to base of climb, (again, good gas mileage stretch) ascend on battery using all charge if necessary, then battery descent the rest of trip going to hold at the end, if necessary, so that you arrive home with "0" charge.
 

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Don’t know if you’re talking about a 130 mile trip from Corvallis (Crater Lake?), but a lot of the non-freeway roads down in that part of Oregon are curvier than straight, which tends to limit the cruising speeds as you wind your way up the mountains, thus limiting the high power demand driving conditions, thus limiting the potential need to borrow power held in the MM-maintained buffer.

The benefit of using Mountain Mode is that you don’t need to remember to switch to Hold Mode if you simply switch into Mountain Mode when you start your trip... in effect, when you switch to MM, you raise the "switch to gas" point to the MM-maintained soc level (~4 bars, you’re in a Gen 1 Volt, right? It’s ~2 bars for Gen 2 Volts). You then drive in Electric Mode until the charge drops to the MM-maintained level, and then the engine starts up and it’s like driving in Hold Mode. Staying in MM until you’ve reached the final pass (i.e., the final uphill stretch) on the way to the destination should be enough to get you where you’re going with no problem.

You don’t need to switch to Normal at the top of a mountain to "bank the regen on the way back down." Regenerative braking is equally effective in Electric Mode and in Extended Range Mode. By the time you reach the bottom of a mountain, regen has raised the battery soc above where it was at the top of the mountain. When you reach level terrain, regardless of mode, you start driving regen battery powered miles until the soc drops to where it was at the top of the mountain (if you came down in Hold Mode, the engine will start again at this point). If you descended in Electric Mode, they’ll count as electric miles. If you descended in Hold Mode, they’ll count as gas miles. The number of regen battery powered miles you get from driving down the mountain doesn’t depend on being in Hold Mode or in Normal mode Downhill regen is "free fuel," so adding those "non-grid electric" miles to your Electric Miles total will improve your ev mileage, adding them to your Gas Miles total will improve your gas mileage.
 

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Discussion Starter #7
Bend is my destination actually.

So basically my understanding is HM is a user defined MM. I may give myself the bigger 50% SOC buffer.

I'm not quite sure how to get an engine temp without an OBD reader. Does a different menu come up when in HM, MM, or REM?
 

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2) You can observe the engine coolant on the Driver Information Console. Normally this would peak at ~205F. If the engine is running hard and the coolant temperature climbs above ~240F you might want to slow down your ascent. .....turning on the cabin heat will help dissipate the excess engine heat.
Just to be clear, this holds true for any ICE car as well. Although any car with good coolant and a clean coolant system should not have any problem climbing most mountain terrain.
 

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The benefit of using Mountain Mode is that you don’t need to remember to switch to Hold Mode if you simply switch into Mountain Mode when you start your trip... in effect, when you switch to MM, you raise the "switch to gas" point to the MM-maintained soc level (~4 bars, you’re in a Gen 1 Volt, right? It’s ~2 bars for Gen 2 Volts). You then drive in Electric Mode until the charge drops to the MM-maintained level, and then the engine starts up and it’s like driving in Hold Mode. Staying in MM until you’ve reached the final pass (i.e., the final uphill stretch) on the way to the destination should be enough to get you where you’re going with no problem.
This is an interesting concept that I never thought of before. Opens up all kinds of possibilities. So leaving it in MM is no different than waiting until you are at 2 bars, and then switching to Hold.
 

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The 2011 - 2012 Gen 1 Volt did not have Hold Mode. Without Hold Mode there was no way to save the battery for later on in your trip such as when climbing a grade. Mountain Mode has always been available. If you were about to start an ascent, about 25 minutes in advance, you would switch to MM and build up a 40% charge so that the electric motors would have some power to assist the gas engine. MM in the Gen 2 Volt is hardly needed as the gas engine in the Gen 2 Volt is more powerful. MM in the Gen 2 works the same as the Gen 1 except you only build up a 15 - 20 % charge.
 

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I regularly travel through the mountains of West Virginia and the Blue Ridge in Virginia (3k Elevation changes and some grades up to 13%). I also have done multiple drives from Virginia to the Catskills in Upstate NY.
Having said that, my most efficient driving techniques have been.

<45mph or stop/start - Battery Power
>45mph and steady (highway) - Switch to hold and let the REX carry things
Very steep curvy grades - Battery power (but I mean the 1-2 mile 13% grades with switchbacks I hit where you don't exceed 35mph)
Long extended grades - HOLD, IF it is a steady speed situation.

Also, unlike the old days where running the A/C might contribute to overheating your engine, in the Volt just use the frikkin A/C. Your battery system will make use of it anyway so if you feel the need to be cool....then be cool! A/C power use is microscopic compared to a lot of other systems (drive and heat)
 

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You aren't going to overtax the engine. There's a YouTube video of a guy going up "the smasher" often seen on Highway Thru Hell TV series (heavy rescue on the Coquihalla) in response to a newspaper article saying the Volt isn't strong enough to do the job. In MM he passes everything in sight going up this steep long upgrade until he reaches then eases off not wanting to pick up a ticket. He's been over many passes in the Canadian Rockies as well as those in the Western States with no problems.

https://www.youtube.com/watch?v=vTWea-C0IW8
 

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On your Gen 1, there is no coolant temperature display.

I think you are overthinking the modes somewhat. What I would do is begin the trip in mountain mode. After passing the peak, switch to normal mode. That is it. This only requires one button press after you begin driving. Keep your mind on the road, not the car. The car is smart enough to manage its self.
 

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You aren't going to overtax the engine. There's a YouTube video of a guy going up "the smasher" often seen on Highway Thru Hell TV series (heavy rescue on the Coquihalla) in response to a newspaper article saying the Volt isn't strong enough to do the job. In MM he passes everything in sight going up this steep long upgrade until he reaches then eases off not wanting to pick up a ticket. He's been over many passes in the Canadian Rockies as well as those in the Western States with no problems.

https://www.youtube.com/watch?v=vTWea-C0IW8
Cool video. I've had my G2 on several mountain trips in the east, but nothing like he did. Given the different configuration, you could run in MM or Hold with a G2, but once the battery was below 2 bars, the engine would be screaming at that speed. Even on slight grades the G2 engine gets pretty loud. Can anyone confirm that?
 

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I’ve made cross-country trips many times with my 2014 Volt, including crossing the Rocky Mountains. I have ALWAYS driven in CS mode, having depleted my battery charge in the first 40 odd miles at the beginning of my trips (I never use the EVSE on my trips). I have only experienced a reduction in speed (65 mph reduced to around 50 mph) ONCE in the Rockies (while driving from Sacramento, California to Wells, Nevada, traversing Donner Pass on I80). That lasted for about one minute until I reached the summit. I’m not sure why that happened…could be that the battery is aging…I had about 70,000+ miles on the odometer at the time. Or, it could have been heavy use of the A/C. I’ll pay closer attention the next time I make that trip.

My current odometer reading is 79283. I may be making another cross-country trip to California in October. The Volt is a terrific road car. I love it.


My recommendation is to not worry about gaming the system. Voltec is going to take care of the car and you without you having to worry about it.
 

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Cool video. I've had my G2 on several mountain trips in the east, but nothing like he did. Given the different configuration, you could run in MM or Hold with a G2, but once the battery was below 2 bars, the engine would be screaming at that speed. Even on slight grades the G2 engine gets pretty loud. Can anyone confirm that?
Just curious, why would the engine be running with 2 bars of electricity left? My Gen 1 doesn't start the engine until the bars are all depleted. Also with the gen1 the engine only has two rpm settings and doesn't use the upper one unless you are running with a depleted battery and are using the electric buffer to below the accepted value. I would suppose the battery use would be the same on a gen2.
 

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Because in Hold Mode or Mountain Mode the Volt is programmed to maintain a battery charge reserve and use the ICE once the minimum battery SOC is reached. In Hold Mode the threshold is set at the SOC when you engage Hold Mode (could be up to ~100% SOC). In Mountain Mode it is programmed to maintain or build up and maintain 40% SOC (4 bars on Gen 1) or 15-20% (2 bars on Gen 2).

If you drove in Normal or Sport mode then the Volt would behave as you expected, deplete the battery to the minimum SOC and then switch to using the ICE.
 

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Because in Hold Mode or Mountain Mode the Volt is programmed to maintain a battery charge reserve and use the ICE once the minimum battery SOC is reached. In Hold Mode the threshold is set at the SOC when you engage Hold Mode (could be up to ~100% SOC). In Mountain Mode it is programmed to maintain or build up and maintain 40% SOC (4 bars on Gen 1) or 15-20% (2 bars on Gen 2).

If you drove in Normal or Sport mode then the Volt would behave as you expected, deplete the battery to the minimum SOC and then switch to using the ICE.
That makes sense, when I engage mountain mode with the battery almost to the bottom bar it will build back up to 16 miles estimate but all I can hear is a sound about equal to a defroster fan on high, doesn't sound like an engine straining to survive.
 

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That makes sense, when I engage mountain mode with the battery almost to the bottom bar it will build back up to 16 miles estimate but all I can hear is a sound about equal to a defroster fan on high, doesn't sound like an engine straining to survive.
Agreed that it's not straining to survive. But going up hill the G2 engine (in Hold or MM) can get pretty loud. If you were accelerating up a really steep mountain highway, I can imagine it would be louder than normal.
 

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>45mph and steady (highway) - Switch to hold and let the REX carry things
Yes. PRESUMING, of course, that you're going to be travelling a fair number of miles on this and would otherwise burn the same fuel at some other point in the trip. Heating the engine up from cold to full operating temperature burns an extra 8-12 ounces, and you don't really want to have to do that more often than you have to, and you can use up to 10% LESS fuel running battery all the way on the trip out, and CS/REX on the way back, versus splitting the gas miles into two highway stretches.
 
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